The present invention relates to a coolant spray nozzle, which is useful as a component for a cutter for machining and metalworking including without limitation a chipforming metalworking operation, as well as the cutter using the coolant spray nozzle. More specifically, the present invention relates to a coolant spray nozzle, which is useful as a component for a milling cutter for machining and metalworking including without limitation a chipforming metalworking operation, as well as the milling cutter (e.g., a multi-pocket milling cutter) using the coolant spray nozzle. Still further, the present invention relates to a coolant spray nozzle, which is useful as a component for a cutter for machining and metalworking including without limitation a chipforming metalworking operation, as well as the cutter using the coolant spray nozzle, wherein there is the capability to facilitate enhanced delivery of coolant adjacent the interface between the cutting (or milling) insert and the workpiece (i.e., the insert-chip interface) to diminish excessive heat at the insert-chip interface in the chipforming removal of material from a workpiece.
Machining and metalworking operations typically include the use of a cutting insert that includes a cutting edge. During the machining and/or metalworking operation, the cutting edge of the cutting insert engages a workpiece at a location characterized as the insert-chip interface. The result is the removal of material from the workpiece in such a fashion to form chips of the workpiece material. Excessive heat at the insert-chip interface can negatively impact upon the overall efficiency of the machining and/or metalworking operation including without limitation a reduction or shortening of the useful tool life of the cutting insert.
In this regard, a chip generated from the workpiece can sometimes stick (e.g., through welding) to the surface of the cutting insert. The build up of chip material on the cutting insert in this fashion is an undesirable occurrence that can negatively impact upon the performance of the cutting insert, and hence, the overall material removal operation. A flow of coolant to the insert-chip interface will reduce the potential for such welding. It would therefore be desirable to reduce excessive heat at the insert-chip interface to eliminate or at least reduce build up of chip material.
As another example, in a chipforming material removal operation, there can occur instances in which the chips do not exit the region of the insert-chip interface when the chip sticks to the cutting insert. When a chip does not exit the region of the insert-chip interface, there is the potential that a chip will be re-cut. It is undesirable for the cutting insert to re-cut a chip already removed from the workpiece. A flow of coolant to the insert-chip interface will facilitate the evacuation of chips from the insert-chip interface thereby minimizing the potential that a chip will be re-cut.
There is an appreciation that a shorter useful tool life increases operating costs and decreases overall production efficiency. Excessive heat at the insert-chip interface contributes to the welding of chip material and re-cutting of chips, both of which are detrimental to production efficiency. There are readily apparent advantages connected with decreasing the heat at the insert-chip interface wherein one way to decrease the temperature is to supply coolant to the insert-chip interface.
One typical way coolant (or cooling fluid) is supplied to the insert-chip interface is by delivery through a passage to a discharge point near the insert-chip interface. For reasons like those set forth above, the cooling fluid serves to prolong the life of the cutting insert, and under certain conditions enables faster cutting or machining of the work piece, by reducing friction and assisting in heat transfer from the work piece to the cutting tool at the insert-chip interface. Heretofore, a number of different coolant delivery systems have been used to supply coolant to the insert-chip interface.
Some coolant delivery systems clamp an exterior tube onto the cutting tool holder to deliver cooling fluid to the cutting tool. While such a system can be inexpensive and easy to assemble, it is suffer drawbacks of being flimsy, easily damaged and incapable of discharging cooling fluid at the desired location, e.g., near the insert-chip interface. Another cooling fluid delivery system provides a coolant duct through the tool holder wherein the coolant duct discharges in an area near the insert-chip interface. However, correct sizing of the coolant ducts presents manufacturing challenges because drilling a long coolant duct with a small drill bit is difficult because the small bit often breaks thereby causing significant downtime and increasing cost. Further, small coolant ducts also take a long time to manufacture due to longer cycle times during the manufacturing operation. To offset the disadvantages with using small drill bits, a manufacturer can use a larger drill bit. Yet, the use of a larger drill bit results in a larger coolant duct that creates a lower system delivery pressure thereby causing poorer coolant delivery and less effective cooling at the insert-chip interface.
Still another coolant delivery system using a coolant spray nozzle is shown and described in United States Patent Application Publication No. US 2009/0214305 A1 for a COOLANT NOZZLES FOR MILLING CUTTER to Waggle et al. and assigned to Kennametal Inc. (the assignee of the present patent application). The structure shown in the Waggle et al. application uses a generally cylindrical coolant duct which terminates with a fixed coolant spray nozzle in the chip gnash of the milling cutter wherein the coolant nozzle sprays coolant in the direction of the insert-chip interface. While the Waggle et al. structure performs adequately, the coolant spray nozzle contains a generally cylindrical coolant bore so as to deliver a generally cylindrically-shape coolant stream. Even though the generally cylindrically-shaped coolant stream may widen to a certain extent after exiting the coolant spray nozzle, the generally cylindrically-shaped coolant stream may not impinge the entire length of the insert-chip interface and certainly does not impinge the entire length of the engaged cutting edge. The failure to impinge the entire length of the insert-chip interface, as well as the entire length of the engaged cutting edge, can result in a reduction in the life of the cutting insert including by means of a catastrophic failure of the cutting insert.
It becomes apparent that it would be highly desirable to provide a coolant spray nozzle, which is useful as a component for a cutter for machining and metalworking including without limitation a chipforming metalworking operation, as well as the cutter using the coolant spray nozzle, wherein there is the capability to facilitate enhanced delivery of coolant adjacent the interface between the cutting (or milling) insert and the workpiece (i.e., the insert-chip interface) by providing a coolant spray that impinges the entire length of the insert-chip interface, as well as the entire length (or substantially all of the entire length) of the engaged cutting edge. Such a coolant spray would diminish excessive heat at the insert-chip interface in the chipforming removal of material from a workpiece, and thereby increase the useful life of the cutting insert by reducing instances of welding chip material to the cutting insert and decreasing the re-cutting of chips, both of which are detrimental to production efficiency.
Further, it is also apparent that it would be highly desirable to provide a coolant spray nozzle, which is useful as a component for a cutter for machining and metalworking including without limitation a chipforming metalworking operation, as well as the cutter using the coolant spray nozzle, wherein there is the capability to facilitate enhanced delivery of coolant adjacent the interface between the cutting (or milling) insert and the workpiece (i.e., the insert-chip interface) by providing for the adjustment of the direction of the coolant spray that impinges the insert-chip interface so as to impinge the entire length of the insert-chip interface, as well as the entire length (or substantially all of the entire length) of the engaged cutting edge. Such a coolant spray would diminish excessive heat at the insert-chip interface in the chipforming removal of material from a workpiece, and thereby increase the useful life of the cutting insert by reducing instances of welding chip material to the cutting insert and decreasing the re-cutting of chips, both of which are detrimental to production efficiency.
In addition, the use of a coolant spray nozzle that provides for the adjustment of the direction of the coolant spray that impinges the insert-chip interface facilitates the ease of manufacturing the cutting body. In this regard, the threaded region of the coolant duct into which the coolant spray nozzle threads does not have to have clocked threads to make certain optimal flow is achieved because the adjustability feature allows for more latitude in the manufacture of the threads. The same holes true for the manufacture of the coolant duct in that there is flexibility in the location thereof due to the adjustability feature of the coolant spray nozzle.